#aardvark-toolbar-button
{
  list-style-image: url("chrome://picsave/skin/toolbar-button.gif");
  -moz-image-region: rect(0px 24px  32px 0px );
}
[iconsize="small"] #aardvark-toolbar-button
{
  -moz-image-region: rect( 0px 40px 24px 24px);
}